I would highly recommend getting a Fitbit if you don’t already have one post surgery. It’s the best way to track your calories, water intake, activity-everything!
I was on a four day stall and went and bought one. After 1 day using it I broke my stall because I was tracking my water better and hitting my steps goal. You can also track your calories which helps tremendously so that you can almost predict what you will lose the next day! Absolutely necessary in my opinion. I bought the new inspire HR it was about 100 bucks. Well worth the investment!

I second that. I've been wearing one for a over a month now. It inspires me to get more exercise.